How to sleep better every night

Convenient or not, it’s a biological fact: adults need to sleep between seven and nine hours each night. A colossal 66 per cent of us fail to do so on a regular basis. It’s not just a matter of feeling tired the next day; over the long run, sleep deprivation can contribute to depression, obesity, diabetes, stroke and heart attacks, and increase your risk of Alzheimer’s disease and cancer.

“The silent sleep-loss epidemic is the greatest public health challenge we face in the 21st century in developed nations,” argues Dr Matthew Walker of the University of California, Berkeley, in his recent book, Why We Sleep. “Scientists like me have even started lobbying doctors to start ‘prescribing’ sleep.”

Walker’s top tip for a successful ‘prescription’ is sticking to a schedule. The body naturally thrives on a regular sleep-wake rhythm, and a set bedtime will remove some of the temptation to spend your time in other ways.

He also recommends avoiding, if at all possible, medicines that could ‘conflict’ with the sleep prescription, such as certain heart, blood pressure or asthma medications, plus some remedies for colds, coughs and allergies. There are alternatives available for many of these drugs, so if they’re costing you shut-eye, speak with your doctor or pharmacist.

If you’ve ever tossed and turned in a hotel room, you may have experience with ‘night-watch brain’.

Cerebral imaging has revealed that, similarly to dolphins, pigeons and other animals, humans rest one half of the brain less than the other when we’re in an unfamiliar setting. This adaptation would have been advantageous for our ancestors, who were at risk of predators in the wild, but it’s far less useful for today’s traveller. You can minimise it by staying at the same hotel for as long as you remain in a city and by booking similar rooms from the same chain wherever you go.

Scientists used to think that dreaming happened only during REM (rapid eye movement), the last stage of the sleep cycle. We now know that earlier stages can bring wisps of dreams as well, but REM is the time of the most detailed, active and emotional ones.

Sleep deprivation is understood to be dangerous, but REM deprivation is also an issue, claims a 2017 review published in the Annals of the New York Academy of Sciences. People with fewer dreams are more subject to mood dysregulation (recurrent temper outbursts or persistent ­extreme irritability), pain sensitivity, Parkinson’s disease, anxiety, dementia and delusions; ironically, dreaming helps you maintain your sense of waking reality.

Dreams are threatened by alcohol, which helps you nod off faster but then disrupts REM. Benzodiazepines (used as sleeping pills or anti-anxiety medi­cation) “significantly repress REM/dreaming”, the review says. ­Another common culprit: alarm clocks. They are often necessary, but try to wake up naturally whenever possible in order to avoid interrupting sleep cycles.

Should you let Spot into your room at night? Mayo Clinic researchers tackled this question by putting accelerom­eters on volunteers and their dogs for one week. Most of the pooches spent some time playing or moving around while their owners dozed. Even so, they didn’t affect the humans’ sleep much – so long as they weren’t allowed up on the bed. A blanket or a pet bed on the floor would be a good compromise if you’d like to enjoy a comforting canine presence without being disturbed.

One of the most common sleep disorders is also a potentially serious one. In obstructive sleep apnoea, the muscles in the back of the throat relax too much during slumber, blocking breathing. This causes drops in blood-oxygen levels that, if left untreated, can strain the cardiovascular system and raise the risk of heart problems over time.

Sufferers will automatically wake long enough to reopen their airways, but they may not remember their episodes come morning. It’s their partners who flag the disorder after noticing snoring, guttural sounds or gasping, says Dr Michael Gelb, a specialist in breathing-related sleep disorders. People who sleep alone can use an app, such as SnoreLab and SnoreReport to record and track snoring. Other­wise, Gelb says, warning signs also include “waking unrefreshed, moodiness, difficulty concentrating, daytime sleepiness and memory problems”.

Sleep-deprivation symptoms aren’t definitive proof that you have sleep apnoea. Nor, for that matter, is snoring, but both are worth investigating. “The diagnosis is ultimately confirmed through a home sleep test or polysomnogram,” says Gelb. “You can organise this through your medical practitioner.”

When it comes to sleeping, there are pros and cons to having a bedmate. Given the common realities of snoring, rolling over and hogging the blankets, tucking in alone will generally garner better results when one’s sleep quality is measured with objective criteria, such as the amount of slow-wave sleep, a non-REM stage that is key to memory consolidation.

Conversely, people tend to be more subjectively satisfied with their shut-eye when they cuddle up next to a loving partner – it releases oxytocin, a feel-good hormone that reduces stress and promotes pair bonding. Here are two ways to reap the benefits while minimising the downsides:

• Make sure your mattress is large enough for two, and if your partner’s movements are an issue, opt for memory foam; you’ll be less likely to feel every toss and turn.
• Work on your partnership. Bad sleep is linked with poor relationship satisfaction and vice versa. It’s an equation that can be tackled from either side.

Although it’s one of the most ­famous sleep disruptors, caffeine can still sneak up on you. “It’s tasteless, so you don’t necessarily know how much you’re getting,” explains Dr Neil Stanley, a member of the European Sleep Research Society. “And it can stick around in your body and affect you for hours if you’re sensitive to it.”

Lesser-known caffeine sources include chocolate, cola soft drinks, some vitamin waters and decaf ­coffee, which simply contains less of the stimulant than a regular cup.

White noise has been proven to mask environmental sounds that disturb slumber. Sleep scientists are now interested in pink noise, which resembles the white variety except that the lower frequencies are louder than the higher ones. There’s evidence that it can enhance slow-wave sleep. In a 2017 study, seniors did better at a recall test after spending a night with pink noise synced up to their slow-wave brain activity. If you’d like to conduct your own ­experiment, you can download a pink noise app.

Which sleeping position is best? Whatever you find comfortable at any given moment, because comfort promotes slumber. Ergonomically speaking, it’s good to mix things up: over the long run, lying the same way every night could lead to aches and pains. If you suffer from…

1. Back or neck pain: Experiment until you find a way to minimise your discomfort. You can use pillows for support.
2. Heartburn Elevate your head by approximately 15 centimetres to stop food from backing up into your oesophagus.
3. Obstructive sleep apnoea Avoid lying on your back, so gravity won’t be working against your airways.

More isn’t always better: regularly sleeping more than nine hours at a time is associated with headaches, back pain, obesity and diabetes. These risks may be due to underlying causes (depression, alcohol abuse and narcolepsy, for example) rather than oversleeping itself. But either way, it’s worth telling your GP.